// https://syzkaller.appspot.com/bug?id=1466684797626866caf7eb7ce1555995744b0238 // autogenerated by syzkaller (https://github.com/google/syzkaller) #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include static __thread int clone_ongoing; static __thread int skip_segv; static __thread jmp_buf segv_env; static void segv_handler(int sig, siginfo_t* info, void* ctx) { if (__atomic_load_n(&clone_ongoing, __ATOMIC_RELAXED) != 0) { exit(sig); } uintptr_t addr = (uintptr_t)info->si_addr; const uintptr_t prog_start = 1 << 20; const uintptr_t prog_end = 100 << 20; int skip = __atomic_load_n(&skip_segv, __ATOMIC_RELAXED) != 0; int valid = addr < prog_start || addr > prog_end; if (skip && valid) { _longjmp(segv_env, 1); } exit(sig); } static void install_segv_handler(void) { struct sigaction sa; memset(&sa, 0, sizeof(sa)); sa.sa_handler = SIG_IGN; syscall(SYS_rt_sigaction, 0x20, &sa, NULL, 8); syscall(SYS_rt_sigaction, 0x21, &sa, NULL, 8); memset(&sa, 0, sizeof(sa)); sa.sa_sigaction = segv_handler; sa.sa_flags = SA_NODEFER | SA_SIGINFO; sigaction(SIGSEGV, &sa, NULL); sigaction(SIGBUS, &sa, NULL); } #define NONFAILING(...) \ ({ \ int ok = 1; \ __atomic_fetch_add(&skip_segv, 1, __ATOMIC_SEQ_CST); \ if (_setjmp(segv_env) == 0) { \ __VA_ARGS__; \ } else \ ok = 0; \ __atomic_fetch_sub(&skip_segv, 1, __ATOMIC_SEQ_CST); \ ok; \ }) uint64_t r[1] = {0xffffffffffffffff}; int main(void) { syscall(__NR_mmap, /*addr=*/0x1ffffffff000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x200000000000ul, /*len=*/0x1000000ul, /*prot=PROT_WRITE|PROT_READ|PROT_EXEC*/ 7ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x200001000000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); const char* reason; (void)reason; install_segv_handler(); intptr_t res = 0; if (write(1, "executing program\n", sizeof("executing program\n") - 1)) { } NONFAILING(*(uint32_t*)0x200000000100 = 0); NONFAILING(*(uint32_t*)0x200000000104 = 0x20); NONFAILING(*(uint64_t*)0x200000000108 = 0x200000000000); NONFAILING(*(uint16_t*)0x200000000000 = 2); NONFAILING(*(uint16_t*)0x200000000002 = htobe16(0x4e24)); NONFAILING(*(uint8_t*)0x200000000004 = 0xac); NONFAILING(*(uint8_t*)0x200000000005 = 0x14); NONFAILING(*(uint8_t*)0x200000000006 = 0x14); NONFAILING(*(uint8_t*)0x200000000007 = 0xaa); NONFAILING(*(uint16_t*)0x200000000010 = 2); NONFAILING(*(uint16_t*)0x200000000012 = htobe16(0x4e20)); NONFAILING(*(uint32_t*)0x200000000014 = htobe32(0xa010101)); syscall(__NR_getsockopt, /*fd=*/(intptr_t)-1, /*level=*/0x84, /*opt=*/0x6f, /*val=*/0x200000000100ul, /*len=*/0ul); NONFAILING(memcpy((void*)0x200000000040, "/dev/comedi4\000", 13)); res = syscall(__NR_openat, /*fd=*/0xffffffffffffff9cul, /*file=*/0x200000000040ul, /*flags=O_SYNC|O_CLOEXEC|O_WRONLY*/ 0x181001, /*mode=*/0); if (res != -1) r[0] = res; syscall(__NR_mprotect, /*addr=*/0x200000000000ul, /*len=*/0x800000ul, /*prot=PROT_READ|PROT_EXEC*/ 5ul); NONFAILING(*(uint32_t*)0x200000000000 = 0); NONFAILING(*(uint64_t*)0x200000000008 = 0); syscall(__NR_ioctl, /*fd=*/r[0], /*cmd=*/0x8010640b, /*arg=*/0x200000000000ul); return 0; }